]> www.ginac.de Git - ginac.git/blobdiff - ginac/power.cpp
documentation update
[ginac.git] / ginac / power.cpp
index fc52a5f814684845d23ba427fcf4216389fce14e..b0f9cd2d293aad258475067ee4693a820e671f9a 100644 (file)
@@ -3,7 +3,7 @@
  *  Implementation of GiNaC's symbolic exponentiation (basis^exponent). */
 
 /*
- *  GiNaC Copyright (C) 1999-2000 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2001 Johannes Gutenberg University Mainz, Germany
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
 #include "debugmsg.h"
 #include "utils.h"
 
-#ifndef NO_NAMESPACE_GINAC
 namespace GiNaC {
-#endif // ndef NO_NAMESPACE_GINAC
 
 GINAC_IMPLEMENT_REGISTERED_CLASS(power, basic)
 
 typedef std::vector<int> intvector;
 
 //////////
-// default constructor, destructor, copy constructor assignment operator and helpers
+// default ctor, dtor, copy ctor assignment operator and helpers
 //////////
 
 // public
 
 power::power() : basic(TINFO_power)
 {
-    debugmsg("power default constructor",LOGLEVEL_CONSTRUCT);
-}
-
-power::~power()
-{
-    debugmsg("power destructor",LOGLEVEL_DESTRUCT);
-    destroy(0);
-}
-
-power::power(const power & other)
-{
-    debugmsg("power copy constructor",LOGLEVEL_CONSTRUCT);
-    copy(other);
-}
-
-const power & power::operator=(const power & other)
-{
-    debugmsg("power operator=",LOGLEVEL_ASSIGNMENT);
-    if (this != &other) {
-        destroy(1);
-        copy(other);
-    }
-    return *this;
+       debugmsg("power default ctor",LOGLEVEL_CONSTRUCT);
 }
 
 // protected
 
 void power::copy(const power & other)
 {
-    inherited::copy(other);
-    basis=other.basis;
-    exponent=other.exponent;
+       inherited::copy(other);
+       basis = other.basis;
+       exponent = other.exponent;
 }
 
 void power::destroy(bool call_parent)
 {
-    if (call_parent) inherited::destroy(call_parent);
+       if (call_parent) inherited::destroy(call_parent);
 }
 
 //////////
-// other constructors
+// other ctors
 //////////
 
 // public
 
 power::power(const ex & lh, const ex & rh) : basic(TINFO_power), basis(lh), exponent(rh)
 {
-    debugmsg("power constructor from ex,ex",LOGLEVEL_CONSTRUCT);
-    GINAC_ASSERT(basis.return_type()==return_types::commutative);
+       debugmsg("power ctor from ex,ex",LOGLEVEL_CONSTRUCT);
+       GINAC_ASSERT(basis.return_type()==return_types::commutative);
 }
 
 power::power(const ex & lh, const numeric & rh) : basic(TINFO_power), basis(lh), exponent(rh)
 {
-    debugmsg("power constructor from ex,numeric",LOGLEVEL_CONSTRUCT);
-    GINAC_ASSERT(basis.return_type()==return_types::commutative);
+       debugmsg("power ctor from ex,numeric",LOGLEVEL_CONSTRUCT);
+       GINAC_ASSERT(basis.return_type()==return_types::commutative);
 }
 
 //////////
@@ -116,23 +92,23 @@ power::power(const ex & lh, const numeric & rh) : basic(TINFO_power), basis(lh),
 /** Construct object from archive_node. */
 power::power(const archive_node &n, const lst &sym_lst) : inherited(n, sym_lst)
 {
-    debugmsg("power constructor from archive_node", LOGLEVEL_CONSTRUCT);
-    n.find_ex("basis", basis, sym_lst);
-    n.find_ex("exponent", exponent, sym_lst);
+       debugmsg("power ctor from archive_node", LOGLEVEL_CONSTRUCT);
+       n.find_ex("basis", basis, sym_lst);
+       n.find_ex("exponent", exponent, sym_lst);
 }
 
 /** Unarchive the object. */
 ex power::unarchive(const archive_node &n, const lst &sym_lst)
 {
-    return (new power(n, sym_lst))->setflag(status_flags::dynallocated);
+       return (new power(n, sym_lst))->setflag(status_flags::dynallocated);
 }
 
 /** Archive the object. */
 void power::archive(archive_node &n) const
 {
-    inherited::archive(n);
-    n.add_ex("basis", basis);
-    n.add_ex("exponent", exponent);
+       inherited::archive(n);
+       n.add_ex("basis", basis);
+       n.add_ex("exponent", exponent);
 }
 
 //////////
@@ -141,380 +117,389 @@ void power::archive(archive_node &n) const
 
 // public
 
-basic * power::duplicate() const
-{
-    debugmsg("power duplicate",LOGLEVEL_DUPLICATE);
-    return new power(*this);
-}
-
 void power::print(std::ostream & os, unsigned upper_precedence) const
 {
-    debugmsg("power print",LOGLEVEL_PRINT);
-    if (exponent.is_equal(_ex1_2())) {
-        os << "sqrt(" << basis << ")";
-    } else {
-        if (precedence<=upper_precedence) os << "(";
-        basis.print(os,precedence);
-        os << "^";
-        exponent.print(os,precedence);
-        if (precedence<=upper_precedence) os << ")";
-    }
+       debugmsg("power print",LOGLEVEL_PRINT);
+       if (exponent.is_equal(_ex1_2())) {
+               os << "sqrt(" << basis << ")";
+       } else {
+               if (precedence<=upper_precedence) os << "(";
+               basis.print(os,precedence);
+               os << "^";
+               exponent.print(os,precedence);
+               if (precedence<=upper_precedence) os << ")";
+       }
 }
 
 void power::printraw(std::ostream & os) const
 {
-    debugmsg("power printraw",LOGLEVEL_PRINT);
+       debugmsg("power printraw",LOGLEVEL_PRINT);
 
-    os << "power(";
-    basis.printraw(os);
-    os << ",";
-    exponent.printraw(os);
-    os << ",hash=" << hashvalue << ",flags=" << flags << ")";
+       os << class_name() << "(";
+       basis.printraw(os);
+       os << ",";
+       exponent.printraw(os);
+       os << ",hash=" << hashvalue << ",flags=" << flags << ")";
 }
 
 void power::printtree(std::ostream & os, unsigned indent) const
 {
-    debugmsg("power printtree",LOGLEVEL_PRINT);
+       debugmsg("power printtree",LOGLEVEL_PRINT);
 
-    os << std::string(indent,' ') << "power: "
-       << "hash=" << hashvalue
-       << " (0x" << std::hex << hashvalue << std::dec << ")"
-       << ", flags=" << flags << std::endl;
-    basis.printtree(os, indent+delta_indent);
-    exponent.printtree(os, indent+delta_indent);
+       os << std::string(indent,' ') << class_name()
+          << ", hash=" << hashvalue
+          << " (0x" << std::hex << hashvalue << std::dec << ")"
+          << ", flags=" << flags << std::endl;
+       basis.printtree(os, indent+delta_indent);
+       exponent.printtree(os, indent+delta_indent);
 }
 
 static void print_sym_pow(std::ostream & os, unsigned type, const symbol &x, int exp)
 {
-    // Optimal output of integer powers of symbols to aid compiler CSE
-    if (exp == 1) {
-        x.printcsrc(os, type, 0);
-    } else if (exp == 2) {
-        x.printcsrc(os, type, 0);
-        os << "*";
-        x.printcsrc(os, type, 0);
-    } else if (exp & 1) {
-        x.printcsrc(os, 0);
-        os << "*";
-        print_sym_pow(os, type, x, exp-1);
-    } else {
-        os << "(";
-        print_sym_pow(os, type, x, exp >> 1);
-        os << ")*(";
-        print_sym_pow(os, type, x, exp >> 1);
-        os << ")";
-    }
+       // Optimal output of integer powers of symbols to aid compiler CSE.
+       // C.f. ISO/IEC 14882:1998, section 1.9 [intro execution], paragraph 15
+       // to learn why such a hack is really necessary.
+       if (exp == 1) {
+               x.printcsrc(os, type, 0);
+       } else if (exp == 2) {
+               x.printcsrc(os, type, 0);
+               os << "*";
+               x.printcsrc(os, type, 0);
+       } else if (exp & 1) {
+               x.printcsrc(os, 0);
+               os << "*";
+               print_sym_pow(os, type, x, exp-1);
+       } else {
+               os << "(";
+               print_sym_pow(os, type, x, exp >> 1);
+               os << ")*(";
+               print_sym_pow(os, type, x, exp >> 1);
+               os << ")";
+       }
 }
 
 void power::printcsrc(std::ostream & os, unsigned type, unsigned upper_precedence) const
 {
-    debugmsg("power print csrc", LOGLEVEL_PRINT);
-    
-    // Integer powers of symbols are printed in a special, optimized way
-    if (exponent.info(info_flags::integer) &&
-        (is_ex_exactly_of_type(basis, symbol) ||
-         is_ex_exactly_of_type(basis, constant))) {
-        int exp = ex_to_numeric(exponent).to_int();
-        if (exp > 0)
-            os << "(";
-        else {
-            exp = -exp;
-            if (type == csrc_types::ctype_cl_N)
-                os << "recip(";
-            else
-                os << "1.0/(";
-        }
-        print_sym_pow(os, type, static_cast<const symbol &>(*basis.bp), exp);
-        os << ")";
-
-    // <expr>^-1 is printed as "1.0/<expr>" or with the recip() function of CLN
-    } else if (exponent.compare(_num_1()) == 0) {
-        if (type == csrc_types::ctype_cl_N)
-            os << "recip(";
-        else
-            os << "1.0/(";
-        basis.bp->printcsrc(os, type, 0);
-        os << ")";
-
-    // Otherwise, use the pow() or expt() (CLN) functions
-    } else {
-        if (type == csrc_types::ctype_cl_N)
-            os << "expt(";
-        else
-            os << "pow(";
-        basis.bp->printcsrc(os, type, 0);
-        os << ",";
-        exponent.bp->printcsrc(os, type, 0);
-        os << ")";
-    }
+       debugmsg("power print csrc", LOGLEVEL_PRINT);
+       
+       // Integer powers of symbols are printed in a special, optimized way
+       if (exponent.info(info_flags::integer)
+        && (is_ex_exactly_of_type(basis, symbol) || is_ex_exactly_of_type(basis, constant))) {
+               int exp = ex_to_numeric(exponent).to_int();
+               if (exp > 0)
+                       os << "(";
+               else {
+                       exp = -exp;
+                       if (type == csrc_types::ctype_cl_N)
+                               os << "recip(";
+                       else
+                               os << "1.0/(";
+               }
+               print_sym_pow(os, type, static_cast<const symbol &>(*basis.bp), exp);
+               os << ")";
+
+       // <expr>^-1 is printed as "1.0/<expr>" or with the recip() function of CLN
+       } else if (exponent.compare(_num_1()) == 0) {
+               if (type == csrc_types::ctype_cl_N)
+                       os << "recip(";
+               else
+                       os << "1.0/(";
+               basis.bp->printcsrc(os, type, 0);
+               os << ")";
+
+       // Otherwise, use the pow() or expt() (CLN) functions
+       } else {
+               if (type == csrc_types::ctype_cl_N)
+                       os << "expt(";
+               else
+                       os << "pow(";
+               basis.bp->printcsrc(os, type, 0);
+               os << ",";
+               exponent.bp->printcsrc(os, type, 0);
+               os << ")";
+       }
 }
 
 bool power::info(unsigned inf) const
 {
-    switch (inf) {
-        case info_flags::polynomial:
-        case info_flags::integer_polynomial:
-        case info_flags::cinteger_polynomial:
-        case info_flags::rational_polynomial:
-        case info_flags::crational_polynomial:
-            return exponent.info(info_flags::nonnegint);
-        case info_flags::rational_function:
-            return exponent.info(info_flags::integer);
-        case info_flags::algebraic:
-            return (!exponent.info(info_flags::integer) ||
-                    basis.info(inf));
-    }
-    return inherited::info(inf);
+       switch (inf) {
+               case info_flags::polynomial:
+               case info_flags::integer_polynomial:
+               case info_flags::cinteger_polynomial:
+               case info_flags::rational_polynomial:
+               case info_flags::crational_polynomial:
+                       return exponent.info(info_flags::nonnegint);
+               case info_flags::rational_function:
+                       return exponent.info(info_flags::integer);
+               case info_flags::algebraic:
+                       return (!exponent.info(info_flags::integer) ||
+                                       basis.info(inf));
+       }
+       return inherited::info(inf);
 }
 
 unsigned power::nops() const
 {
-    return 2;
+       return 2;
 }
 
 ex & power::let_op(int i)
 {
-    GINAC_ASSERT(i>=0);
-    GINAC_ASSERT(i<2);
+       GINAC_ASSERT(i>=0);
+       GINAC_ASSERT(i<2);
 
-    return i==0 ? basis : exponent;
+       return i==0 ? basis : exponent;
 }
 
 int power::degree(const symbol & s) const
 {
-    if (is_exactly_of_type(*exponent.bp,numeric)) {
-        if ((*basis.bp).compare(s)==0)
-            return ex_to_numeric(exponent).to_int();
-        else
-            return basis.degree(s) * ex_to_numeric(exponent).to_int();
-    }
-    return 0;
+       if (is_exactly_of_type(*exponent.bp,numeric)) {
+               if ((*basis.bp).compare(s)==0) {
+                       if (ex_to_numeric(exponent).is_integer())
+                               return ex_to_numeric(exponent).to_int();
+                       else
+                               return 0;
+               } else
+                       return basis.degree(s) * ex_to_numeric(exponent).to_int();
+       }
+       return 0;
 }
 
 int power::ldegree(const symbol & s) const 
 {
-    if (is_exactly_of_type(*exponent.bp,numeric)) {
-        if ((*basis.bp).compare(s)==0)
-            return ex_to_numeric(exponent).to_int();
-        else
-            return basis.ldegree(s) * ex_to_numeric(exponent).to_int();
-    }
-    return 0;
+       if (is_exactly_of_type(*exponent.bp,numeric)) {
+               if ((*basis.bp).compare(s)==0) {
+                       if (ex_to_numeric(exponent).is_integer())
+                               return ex_to_numeric(exponent).to_int();
+                       else
+                               return 0;
+               } else
+                       return basis.ldegree(s) * ex_to_numeric(exponent).to_int();
+       }
+       return 0;
 }
 
 ex power::coeff(const symbol & s, int n) const
 {
-    if ((*basis.bp).compare(s)!=0) {
-        // basis not equal to s
-        if (n==0) {
-            return *this;
-        } else {
-            return _ex0();
-        }
-    } else if (is_exactly_of_type(*exponent.bp,numeric)&&
-               (static_cast<const numeric &>(*exponent.bp).compare(numeric(n))==0)) {
-        return _ex1();
-    }
-
-    return _ex0();
+       if ((*basis.bp).compare(s)!=0) {
+               // basis not equal to s
+               if (n == 0)
+                       return *this;
+               else
+                       return _ex0();
+       } else {
+               // basis equal to s
+               if (is_exactly_of_type(*exponent.bp, numeric) && ex_to_numeric(exponent).is_integer()) {
+                       // integer exponent
+                       int int_exp = ex_to_numeric(exponent).to_int();
+                       if (n == int_exp)
+                               return _ex1();
+                       else
+                               return _ex0();
+               } else {
+                       // non-integer exponents are treated as zero
+                       if (n == 0)
+                               return *this;
+                       else
+                               return _ex0();
+               }
+       }
 }
 
 ex power::eval(int level) const
 {
-    // simplifications: ^(x,0) -> 1 (0^0 handled here)
-    //                  ^(x,1) -> x
-    //                  ^(0,c1) -> 0 or exception (depending on real value of c1)
-    //                  ^(1,x) -> 1
-    //                  ^(c1,c2) -> *(c1^n,c1^(c2-n)) (c1, c2 numeric(), 0<(c2-n)<1 except if c1,c2 are rational, but c1^c2 is not)
-    //                  ^(^(x,c1),c2) -> ^(x,c1*c2) (c1, c2 numeric(), c2 integer or -1 < c1 <= 1, case c1=1 should not happen, see below!)
-    //                  ^(*(x,y,z),c1) -> *(x^c1,y^c1,z^c1) (c1 integer)
-    //                  ^(*(x,c1),c2) -> ^(x,c2)*c1^c2 (c1, c2 numeric(), c1>0)
-    //                  ^(*(x,c1),c2) -> ^(-x,c2)*c1^c2 (c1, c2 numeric(), c1<0)
-    
-    debugmsg("power eval",LOGLEVEL_MEMBER_FUNCTION);
-    
-    if ((level==1) && (flags & status_flags::evaluated))
-        return *this;
-    else if (level == -max_recursion_level)
-        throw(std::runtime_error("max recursion level reached"));
-    
-    const ex & ebasis    = level==1 ? basis    : basis.eval(level-1);
-    const ex & eexponent = level==1 ? exponent : exponent.eval(level-1);
-    
-    bool basis_is_numerical = 0;
-    bool exponent_is_numerical = 0;
-    numeric * num_basis;
-    numeric * num_exponent;
-    
-    if (is_exactly_of_type(*ebasis.bp,numeric)) {
-        basis_is_numerical = 1;
-        num_basis = static_cast<numeric *>(ebasis.bp);
-    }
-    if (is_exactly_of_type(*eexponent.bp,numeric)) {
-        exponent_is_numerical = 1;
-        num_exponent = static_cast<numeric *>(eexponent.bp);
-    }
-    
-    // ^(x,0) -> 1 (0^0 also handled here)
-    if (eexponent.is_zero())
-        if (ebasis.is_zero())
-            throw (std::domain_error("power::eval(): pow(0,0) is undefined"));
-        else
-            return _ex1();
-    
-    // ^(x,1) -> x
-    if (eexponent.is_equal(_ex1()))
-        return ebasis;
-    
-    // ^(0,c1) -> 0 or exception (depending on real value of c1)
-    if (ebasis.is_zero() && exponent_is_numerical) {
-        if ((num_exponent->real()).is_zero())
-            throw (std::domain_error("power::eval(): pow(0,I) is undefined"));
-        else if ((num_exponent->real()).is_negative())
-            throw (pole_error("power::eval(): division by zero",1));
-        else
-            return _ex0();
-    }
-    
-    // ^(1,x) -> 1
-    if (ebasis.is_equal(_ex1()))
-        return _ex1();
-    
-    if (basis_is_numerical && exponent_is_numerical) {
-        // ^(c1,c2) -> c1^c2 (c1, c2 numeric(),
-        // except if c1,c2 are rational, but c1^c2 is not)
-        bool basis_is_crational = num_basis->is_crational();
-        bool exponent_is_crational = num_exponent->is_crational();
-        numeric res = (*num_basis).power(*num_exponent);
-        
-        if ((!basis_is_crational || !exponent_is_crational)
-            || res.is_crational()) {
-            return res;
-        }
-        GINAC_ASSERT(!num_exponent->is_integer());  // has been handled by now
-        // ^(c1,n/m) -> *(c1^q,c1^(n/m-q)), 0<(n/m-h)<1, q integer
-        if (basis_is_crational && exponent_is_crational
-            && num_exponent->is_real()
-            && !num_exponent->is_integer()) {
-            numeric n = num_exponent->numer();
-            numeric m = num_exponent->denom();
-            numeric r;
-            numeric q = iquo(n, m, r);
-            if (r.is_negative()) {
-                r = r.add(m);
-                q = q.sub(_num1());
-            }
-            if (q.is_zero())  // the exponent was in the allowed range 0<(n/m)<1
-                return this->hold();
-            else {
-                epvector res;
-                res.push_back(expair(ebasis,r.div(m)));
-                return (new mul(res,ex(num_basis->power(q))))->setflag(status_flags::dynallocated | status_flags::evaluated);
-            }
-        }
-    }
-    
-    // ^(^(x,c1),c2) -> ^(x,c1*c2)
-    // (c1, c2 numeric(), c2 integer or -1 < c1 <= 1,
-    // case c1==1 should not happen, see below!)
-    if (exponent_is_numerical && is_ex_exactly_of_type(ebasis,power)) {
-        const power & sub_power = ex_to_power(ebasis);
-        const ex & sub_basis = sub_power.basis;
-        const ex & sub_exponent = sub_power.exponent;
-        if (is_ex_exactly_of_type(sub_exponent,numeric)) {
-            const numeric & num_sub_exponent = ex_to_numeric(sub_exponent);
-            GINAC_ASSERT(num_sub_exponent!=numeric(1));
-            if (num_exponent->is_integer() || abs(num_sub_exponent)<1) {
-                return power(sub_basis,num_sub_exponent.mul(*num_exponent));
-            }
-        }
-    }
-    
-    // ^(*(x,y,z),c1) -> *(x^c1,y^c1,z^c1) (c1 integer)
-    if (exponent_is_numerical && num_exponent->is_integer() &&
-        is_ex_exactly_of_type(ebasis,mul)) {
-        return expand_mul(ex_to_mul(ebasis), *num_exponent);
-    }
-    
-    // ^(*(...,x;c1),c2) -> ^(*(...,x;1),c2)*c1^c2 (c1, c2 numeric(), c1>0)
-    // ^(*(...,x,c1),c2) -> ^(*(...,x;-1),c2)*(-c1)^c2 (c1, c2 numeric(), c1<0)
-    if (exponent_is_numerical && is_ex_exactly_of_type(ebasis,mul)) {
-        GINAC_ASSERT(!num_exponent->is_integer()); // should have been handled above
-        const mul & mulref=ex_to_mul(ebasis);
-        if (!mulref.overall_coeff.is_equal(_ex1())) {
-            const numeric & num_coeff=ex_to_numeric(mulref.overall_coeff);
-            if (num_coeff.is_real()) {
-                if (num_coeff.is_positive()>0) {
-                    mul * mulp=new mul(mulref);
-                    mulp->overall_coeff=_ex1();
-                    mulp->clearflag(status_flags::evaluated);
-                    mulp->clearflag(status_flags::hash_calculated);
-                    return (new mul(power(*mulp,exponent),
-                                    power(num_coeff,*num_exponent)))->
-                        setflag(status_flags::dynallocated);
-                } else {
-                    GINAC_ASSERT(num_coeff.compare(_num0())<0);
-                    if (num_coeff.compare(_num_1())!=0) {
-                        mul * mulp=new mul(mulref);
-                        mulp->overall_coeff=_ex_1();
-                        mulp->clearflag(status_flags::evaluated);
-                        mulp->clearflag(status_flags::hash_calculated);
-                        return (new mul(power(*mulp,exponent),
-                                        power(abs(num_coeff),*num_exponent)))->
-                            setflag(status_flags::dynallocated);
-                    }
-                }
-            }
-        }
-    }
-        
-    if (are_ex_trivially_equal(ebasis,basis) &&
-        are_ex_trivially_equal(eexponent,exponent)) {
-        return this->hold();
-    }
-    return (new power(ebasis, eexponent))->setflag(status_flags::dynallocated |
-                                                   status_flags::evaluated);
+       // simplifications: ^(x,0) -> 1 (0^0 handled here)
+       //                  ^(x,1) -> x
+       //                  ^(0,c1) -> 0 or exception (depending on real value of c1)
+       //                  ^(1,x) -> 1
+       //                  ^(c1,c2) -> *(c1^n,c1^(c2-n)) (c1, c2 numeric(), 0<(c2-n)<1 except if c1,c2 are rational, but c1^c2 is not)
+       //                  ^(^(x,c1),c2) -> ^(x,c1*c2) (c1, c2 numeric(), c2 integer or -1 < c1 <= 1, case c1=1 should not happen, see below!)
+       //                  ^(*(x,y,z),c1) -> *(x^c1,y^c1,z^c1) (c1 integer)
+       //                  ^(*(x,c1),c2) -> ^(x,c2)*c1^c2 (c1, c2 numeric(), c1>0)
+       //                  ^(*(x,c1),c2) -> ^(-x,c2)*c1^c2 (c1, c2 numeric(), c1<0)
+       
+       debugmsg("power eval",LOGLEVEL_MEMBER_FUNCTION);
+       
+       if ((level==1) && (flags & status_flags::evaluated))
+               return *this;
+       else if (level == -max_recursion_level)
+               throw(std::runtime_error("max recursion level reached"));
+       
+       const ex & ebasis    = level==1 ? basis    : basis.eval(level-1);
+       const ex & eexponent = level==1 ? exponent : exponent.eval(level-1);
+       
+       bool basis_is_numerical = 0;
+       bool exponent_is_numerical = 0;
+       numeric * num_basis;
+       numeric * num_exponent;
+       
+       if (is_exactly_of_type(*ebasis.bp,numeric)) {
+               basis_is_numerical = 1;
+               num_basis = static_cast<numeric *>(ebasis.bp);
+       }
+       if (is_exactly_of_type(*eexponent.bp,numeric)) {
+               exponent_is_numerical = 1;
+               num_exponent = static_cast<numeric *>(eexponent.bp);
+       }
+       
+       // ^(x,0) -> 1 (0^0 also handled here)
+       if (eexponent.is_zero()) {
+               if (ebasis.is_zero())
+                       throw (std::domain_error("power::eval(): pow(0,0) is undefined"));
+               else
+                       return _ex1();
+       }
+       
+       // ^(x,1) -> x
+       if (eexponent.is_equal(_ex1()))
+               return ebasis;
+       
+       // ^(0,c1) -> 0 or exception (depending on real value of c1)
+       if (ebasis.is_zero() && exponent_is_numerical) {
+               if ((num_exponent->real()).is_zero())
+                       throw (std::domain_error("power::eval(): pow(0,I) is undefined"));
+               else if ((num_exponent->real()).is_negative())
+                       throw (pole_error("power::eval(): division by zero",1));
+               else
+                       return _ex0();
+       }
+       
+       // ^(1,x) -> 1
+       if (ebasis.is_equal(_ex1()))
+               return _ex1();
+       
+       if (basis_is_numerical && exponent_is_numerical) {
+               // ^(c1,c2) -> c1^c2 (c1, c2 numeric(),
+               // except if c1,c2 are rational, but c1^c2 is not)
+               bool basis_is_crational = num_basis->is_crational();
+               bool exponent_is_crational = num_exponent->is_crational();
+               numeric res = num_basis->power(*num_exponent);
+               
+               if ((!basis_is_crational || !exponent_is_crational)
+                       || res.is_crational()) {
+                       return res;
+               }
+               GINAC_ASSERT(!num_exponent->is_integer());  // has been handled by now
+               // ^(c1,n/m) -> *(c1^q,c1^(n/m-q)), 0<(n/m-h)<1, q integer
+               if (basis_is_crational && exponent_is_crational
+                       && num_exponent->is_real()
+                       && !num_exponent->is_integer()) {
+                       numeric n = num_exponent->numer();
+                       numeric m = num_exponent->denom();
+                       numeric r;
+                       numeric q = iquo(n, m, r);
+                       if (r.is_negative()) {
+                               r = r.add(m);
+                               q = q.sub(_num1());
+                       }
+                       if (q.is_zero())  // the exponent was in the allowed range 0<(n/m)<1
+                               return this->hold();
+                       else {
+                               epvector res;
+                               res.push_back(expair(ebasis,r.div(m)));
+                               return (new mul(res,ex(num_basis->power_dyn(q))))->setflag(status_flags::dynallocated | status_flags::evaluated);
+                       }
+               }
+       }
+       
+       // ^(^(x,c1),c2) -> ^(x,c1*c2)
+       // (c1, c2 numeric(), c2 integer or -1 < c1 <= 1,
+       // case c1==1 should not happen, see below!)
+       if (exponent_is_numerical && is_ex_exactly_of_type(ebasis,power)) {
+               const power & sub_power = ex_to_power(ebasis);
+               const ex & sub_basis = sub_power.basis;
+               const ex & sub_exponent = sub_power.exponent;
+               if (is_ex_exactly_of_type(sub_exponent,numeric)) {
+                       const numeric & num_sub_exponent = ex_to_numeric(sub_exponent);
+                       GINAC_ASSERT(num_sub_exponent!=numeric(1));
+                       if (num_exponent->is_integer() || abs(num_sub_exponent)<1)
+                               return power(sub_basis,num_sub_exponent.mul(*num_exponent));
+               }
+       }
+       
+       // ^(*(x,y,z),c1) -> *(x^c1,y^c1,z^c1) (c1 integer)
+       if (exponent_is_numerical && num_exponent->is_integer() &&
+               is_ex_exactly_of_type(ebasis,mul)) {
+               return expand_mul(ex_to_mul(ebasis), *num_exponent);
+       }
+       
+       // ^(*(...,x;c1),c2) -> ^(*(...,x;1),c2)*c1^c2 (c1, c2 numeric(), c1>0)
+       // ^(*(...,x,c1),c2) -> ^(*(...,x;-1),c2)*(-c1)^c2 (c1, c2 numeric(), c1<0)
+       if (exponent_is_numerical && is_ex_exactly_of_type(ebasis,mul)) {
+               GINAC_ASSERT(!num_exponent->is_integer()); // should have been handled above
+               const mul & mulref = ex_to_mul(ebasis);
+               if (!mulref.overall_coeff.is_equal(_ex1())) {
+                       const numeric & num_coeff = ex_to_numeric(mulref.overall_coeff);
+                       if (num_coeff.is_real()) {
+                               if (num_coeff.is_positive()) {
+                                       mul * mulp = new mul(mulref);
+                                       mulp->overall_coeff = _ex1();
+                                       mulp->clearflag(status_flags::evaluated);
+                                       mulp->clearflag(status_flags::hash_calculated);
+                                       return (new mul(power(*mulp,exponent),
+                                                       power(num_coeff,*num_exponent)))->setflag(status_flags::dynallocated);
+                               } else {
+                                       GINAC_ASSERT(num_coeff.compare(_num0())<0);
+                                       if (num_coeff.compare(_num_1())!=0) {
+                                               mul * mulp = new mul(mulref);
+                                               mulp->overall_coeff = _ex_1();
+                                               mulp->clearflag(status_flags::evaluated);
+                                               mulp->clearflag(status_flags::hash_calculated);
+                                               return (new mul(power(*mulp,exponent),
+                                                               power(abs(num_coeff),*num_exponent)))->setflag(status_flags::dynallocated);
+                                       }
+                               }
+                       }
+               }
+       }
+       
+       if (are_ex_trivially_equal(ebasis,basis) &&
+               are_ex_trivially_equal(eexponent,exponent)) {
+               return this->hold();
+       }
+       return (new power(ebasis, eexponent))->setflag(status_flags::dynallocated |
+                                                                                                  status_flags::evaluated);
 }
 
 ex power::evalf(int level) const
 {
-    debugmsg("power evalf",LOGLEVEL_MEMBER_FUNCTION);
+       debugmsg("power evalf",LOGLEVEL_MEMBER_FUNCTION);
 
-    ex ebasis;
-    ex eexponent;
-    
-    if (level==1) {
-        ebasis = basis;
-        eexponent = exponent;
-    } else if (level == -max_recursion_level) {
-        throw(std::runtime_error("max recursion level reached"));
-    } else {
-        ebasis = basis.evalf(level-1);
-        if (!is_ex_exactly_of_type(eexponent,numeric))
-            eexponent = exponent.evalf(level-1);
-        else
-            eexponent = exponent;
-    }
+       ex ebasis;
+       ex eexponent;
+       
+       if (level==1) {
+               ebasis = basis;
+               eexponent = exponent;
+       } else if (level == -max_recursion_level) {
+               throw(std::runtime_error("max recursion level reached"));
+       } else {
+               ebasis = basis.evalf(level-1);
+               if (!is_ex_exactly_of_type(eexponent,numeric))
+                       eexponent = exponent.evalf(level-1);
+               else
+                       eexponent = exponent;
+       }
 
-    return power(ebasis,eexponent);
+       return power(ebasis,eexponent);
 }
 
 ex power::subs(const lst & ls, const lst & lr) const
 {
-    const ex & subsed_basis=basis.subs(ls,lr);
-    const ex & subsed_exponent=exponent.subs(ls,lr);
+       const ex & subsed_basis=basis.subs(ls,lr);
+       const ex & subsed_exponent=exponent.subs(ls,lr);
 
-    if (are_ex_trivially_equal(basis,subsed_basis)&&
-        are_ex_trivially_equal(exponent,subsed_exponent)) {
-        return *this;
-    }
-    
-    return power(subsed_basis, subsed_exponent);
+       if (are_ex_trivially_equal(basis,subsed_basis)&&
+               are_ex_trivially_equal(exponent,subsed_exponent)) {
+               return *this;
+       }
+       
+       return power(subsed_basis, subsed_exponent);
 }
 
 ex power::simplify_ncmul(const exvector & v) const
 {
-    return inherited::simplify_ncmul(v);
+       return inherited::simplify_ncmul(v);
 }
 
 // protected
@@ -523,83 +508,106 @@ ex power::simplify_ncmul(const exvector & v) const
  *  @see ex::diff */
 ex power::derivative(const symbol & s) const
 {
-    if (exponent.info(info_flags::real)) {
-        // D(b^r) = r * b^(r-1) * D(b) (faster than the formula below)
-        //return mul(mul(exponent, power(basis, exponent - _ex1())), basis.diff(s));
-        epvector newseq;
-        newseq.reserve(2);
-        newseq.push_back(expair(basis, exponent - _ex1()));
-        newseq.push_back(expair(basis.diff(s),_ex1()));
-        return mul(newseq, exponent);
-    } else {
-        // D(b^e) = b^e * (D(e)*ln(b) + e*D(b)/b)
-        return mul(power(basis, exponent),
-                   add(mul(exponent.diff(s), log(basis)),
-                       mul(mul(exponent, basis.diff(s)), power(basis, -1))));
-    }
+       if (exponent.info(info_flags::real)) {
+               // D(b^r) = r * b^(r-1) * D(b) (faster than the formula below)
+               epvector newseq;
+               newseq.reserve(2);
+               newseq.push_back(expair(basis, exponent - _ex1()));
+               newseq.push_back(expair(basis.diff(s), _ex1()));
+               return mul(newseq, exponent);
+       } else {
+               // D(b^e) = b^e * (D(e)*ln(b) + e*D(b)/b)
+               return mul(*this,
+                          add(mul(exponent.diff(s), log(basis)),
+                          mul(mul(exponent, basis.diff(s)), power(basis, _ex_1()))));
+       }
 }
 
 int power::compare_same_type(const basic & other) const
 {
-    GINAC_ASSERT(is_exactly_of_type(other, power));
-    const power & o=static_cast<const power &>(const_cast<basic &>(other));
+       GINAC_ASSERT(is_exactly_of_type(other, power));
+       const power & o=static_cast<const power &>(const_cast<basic &>(other));
 
-    int cmpval;
-    cmpval=basis.compare(o.basis);
-    if (cmpval==0) {
-        return exponent.compare(o.exponent);
-    }
-    return cmpval;
+       int cmpval;
+       cmpval=basis.compare(o.basis);
+       if (cmpval==0) {
+               return exponent.compare(o.exponent);
+       }
+       return cmpval;
 }
 
 unsigned power::return_type(void) const
 {
-    return basis.return_type();
+       return basis.return_type();
 }
    
 unsigned power::return_type_tinfo(void) const
 {
-    return basis.return_type_tinfo();
+       return basis.return_type_tinfo();
 }
 
 ex power::expand(unsigned options) const
 {
-    if (flags & status_flags::expanded)
-        return *this;
-    
-    ex expanded_basis = basis.expand(options);
-    
-    if (!is_ex_exactly_of_type(exponent,numeric) ||
-        !ex_to_numeric(exponent).is_integer()) {
-        if (are_ex_trivially_equal(basis,expanded_basis)) {
-            return this->hold();
-        } else {
-            return (new power(expanded_basis,exponent))->
-                setflag(status_flags::dynallocated |
-                        status_flags::expanded);
-        }
-    }
-    
-    // integer numeric exponent
-    const numeric & num_exponent = ex_to_numeric(exponent);
-    int int_exponent = num_exponent.to_int();
-    
-    if (int_exponent > 0 && is_ex_exactly_of_type(expanded_basis,add)) {
-        return expand_add(ex_to_add(expanded_basis), int_exponent);
-    }
-    
-    if (is_ex_exactly_of_type(expanded_basis,mul)) {
-        return expand_mul(ex_to_mul(expanded_basis), num_exponent);
-    }
-    
-    // cannot expand further
-    if (are_ex_trivially_equal(basis,expanded_basis)) {
-        return this->hold();
-    } else {
-        return (new power(expanded_basis,exponent))->
-               setflag(status_flags::dynallocated |
-                       status_flags::expanded);
-    }
+       if (flags & status_flags::expanded)
+               return *this;
+       
+       ex expanded_basis = basis.expand(options);
+       ex expanded_exponent = exponent.expand(options);
+       
+       // x^(a+b) -> x^a * x^b
+       if (is_ex_exactly_of_type(expanded_exponent, add)) {
+               const add &a = ex_to_add(expanded_exponent);
+               exvector distrseq;
+               distrseq.reserve(a.seq.size() + 1);
+               epvector::const_iterator last = a.seq.end();
+               epvector::const_iterator cit = a.seq.begin();
+               while (cit!=last) {
+                       distrseq.push_back(power(expanded_basis, a.recombine_pair_to_ex(*cit)));
+                       cit++;
+               }
+               
+               // Make sure that e.g. (x+y)^(2+a) expands the (x+y)^2 factor
+               if (ex_to_numeric(a.overall_coeff).is_integer()) {
+                       const numeric &num_exponent = ex_to_numeric(a.overall_coeff);
+                       int int_exponent = num_exponent.to_int();
+                       if (int_exponent > 0 && is_ex_exactly_of_type(expanded_basis, add))
+                               distrseq.push_back(expand_add(ex_to_add(expanded_basis), int_exponent));
+                       else
+                               distrseq.push_back(power(expanded_basis, a.overall_coeff));
+               } else
+                       distrseq.push_back(power(expanded_basis, a.overall_coeff));
+               
+               // Make sure that e.g. (x+y)^(1+a) -> x*(x+y)^a + y*(x+y)^a
+               ex r = (new mul(distrseq))->setflag(status_flags::dynallocated);
+               return r.expand();
+       }
+       
+       if (!is_ex_exactly_of_type(expanded_exponent, numeric) ||
+               !ex_to_numeric(expanded_exponent).is_integer()) {
+               if (are_ex_trivially_equal(basis,expanded_basis) && are_ex_trivially_equal(exponent,expanded_exponent)) {
+                       return this->hold();
+               } else {
+                       return (new power(expanded_basis,expanded_exponent))->setflag(status_flags::dynallocated | status_flags::expanded);
+               }
+       }
+       
+       // integer numeric exponent
+       const numeric & num_exponent = ex_to_numeric(expanded_exponent);
+       int int_exponent = num_exponent.to_int();
+       
+       // (x+y)^n, n>0
+       if (int_exponent > 0 && is_ex_exactly_of_type(expanded_basis,add))
+               return expand_add(ex_to_add(expanded_basis), int_exponent);
+       
+       // (x*y)^n -> x^n * y^n
+       if (is_ex_exactly_of_type(expanded_basis,mul))
+               return expand_mul(ex_to_mul(expanded_basis), num_exponent);
+       
+       // cannot expand further
+       if (are_ex_trivially_equal(basis,expanded_basis) && are_ex_trivially_equal(exponent,expanded_exponent))
+               return this->hold();
+       else
+               return (new power(expanded_basis,expanded_exponent))->setflag(status_flags::dynallocated | status_flags::expanded);
 }
 
 //////////
@@ -616,102 +624,98 @@ ex power::expand(unsigned options) const
  *  @see power::expand */
 ex power::expand_add(const add & a, int n) const
 {
-    if (n==2)
-        return expand_add_2(a);
-    
-    int m = a.nops();
-    exvector sum;
-    sum.reserve((n+1)*(m-1));
-    intvector k(m-1);
-    intvector k_cum(m-1); // k_cum[l]:=sum(i=0,l,k[l]);
-    intvector upper_limit(m-1);
-    int l;
-    
-    for (int l=0; l<m-1; l++) {
-        k[l] = 0;
-        k_cum[l] = 0;
-        upper_limit[l] = n;
-    }
-    
-    while (1) {
-        exvector term;
-        term.reserve(m+1);
-        for (l=0; l<m-1; l++) {
-            const ex & b = a.op(l);
-            GINAC_ASSERT(!is_ex_exactly_of_type(b,add));
-            GINAC_ASSERT(!is_ex_exactly_of_type(b,power)||
-                         !is_ex_exactly_of_type(ex_to_power(b).exponent,numeric)||
-                         !ex_to_numeric(ex_to_power(b).exponent).is_pos_integer()||
-                         !is_ex_exactly_of_type(ex_to_power(b).basis,add)||
-                         !is_ex_exactly_of_type(ex_to_power(b).basis,mul)||
-                         !is_ex_exactly_of_type(ex_to_power(b).basis,power));
-            if (is_ex_exactly_of_type(b,mul)) {
-                term.push_back(expand_mul(ex_to_mul(b),numeric(k[l])));
-            } else {
-                term.push_back(power(b,k[l]));
-            }
-        }
-        
-        const ex & b = a.op(l);
-        GINAC_ASSERT(!is_ex_exactly_of_type(b,add));
-        GINAC_ASSERT(!is_ex_exactly_of_type(b,power)||
-                     !is_ex_exactly_of_type(ex_to_power(b).exponent,numeric)||
-                     !ex_to_numeric(ex_to_power(b).exponent).is_pos_integer()||
-                     !is_ex_exactly_of_type(ex_to_power(b).basis,add)||
-                     !is_ex_exactly_of_type(ex_to_power(b).basis,mul)||
-                     !is_ex_exactly_of_type(ex_to_power(b).basis,power));
-        if (is_ex_exactly_of_type(b,mul)) {
-            term.push_back(expand_mul(ex_to_mul(b),numeric(n-k_cum[m-2])));
-        } else {
-            term.push_back(power(b,n-k_cum[m-2]));
-        }
-        
-        numeric f = binomial(numeric(n),numeric(k[0]));
-        for (l=1; l<m-1; l++) {
-            f=f*binomial(numeric(n-k_cum[l-1]),numeric(k[l]));
-        }
-        term.push_back(f);
-
-        /*
-        cout << "begin term" << endl;
-        for (int i=0; i<m-1; i++) {
-            cout << "k[" << i << "]=" << k[i] << endl;
-            cout << "k_cum[" << i << "]=" << k_cum[i] << endl;
-            cout << "upper_limit[" << i << "]=" << upper_limit[i] << endl;
-        }
-        for (exvector::const_iterator cit=term.begin(); cit!=term.end(); ++cit) {
-            cout << *cit << endl;
-        }
-        cout << "end term" << endl;
-        */
-
-        // TODO: optimize this
-        sum.push_back((new mul(term))->setflag(status_flags::dynallocated));
-        
-        // increment k[]
-        l=m-2;
-        while ((l>=0)&&((++k[l])>upper_limit[l])) {
-            k[l]=0;    
-            l--;
-        }
-        if (l<0) break;
-
-        // recalc k_cum[] and upper_limit[]
-        if (l==0) {
-            k_cum[0]=k[0];
-        } else {
-            k_cum[l]=k_cum[l-1]+k[l];
-        }
-        for (int i=l+1; i<m-1; i++) {
-            k_cum[i]=k_cum[i-1]+k[i];
-        }
-
-        for (int i=l+1; i<m-1; i++) {
-            upper_limit[i]=n-k_cum[i-1];
-        }   
-    }
-    return (new add(sum))->setflag(status_flags::dynallocated |
-                                   status_flags::expanded );
+       if (n==2)
+               return expand_add_2(a);
+       
+       int m = a.nops();
+       exvector sum;
+       sum.reserve((n+1)*(m-1));
+       intvector k(m-1);
+       intvector k_cum(m-1); // k_cum[l]:=sum(i=0,l,k[l]);
+       intvector upper_limit(m-1);
+       int l;
+       
+       for (int l=0; l<m-1; l++) {
+               k[l] = 0;
+               k_cum[l] = 0;
+               upper_limit[l] = n;
+       }
+       
+       while (1) {
+               exvector term;
+               term.reserve(m+1);
+               for (l=0; l<m-1; l++) {
+                       const ex & b = a.op(l);
+                       GINAC_ASSERT(!is_ex_exactly_of_type(b,add));
+                       GINAC_ASSERT(!is_ex_exactly_of_type(b,power) ||
+                                    !is_ex_exactly_of_type(ex_to_power(b).exponent,numeric) ||
+                                    !ex_to_numeric(ex_to_power(b).exponent).is_pos_integer() ||
+                                    !is_ex_exactly_of_type(ex_to_power(b).basis,add) ||
+                                    !is_ex_exactly_of_type(ex_to_power(b).basis,mul) ||
+                                    !is_ex_exactly_of_type(ex_to_power(b).basis,power));
+                       if (is_ex_exactly_of_type(b,mul))
+                               term.push_back(expand_mul(ex_to_mul(b),numeric(k[l])));
+                       else
+                               term.push_back(power(b,k[l]));
+               }
+               
+               const ex & b = a.op(l);
+               GINAC_ASSERT(!is_ex_exactly_of_type(b,add));
+               GINAC_ASSERT(!is_ex_exactly_of_type(b,power) ||
+                            !is_ex_exactly_of_type(ex_to_power(b).exponent,numeric) ||
+                            !ex_to_numeric(ex_to_power(b).exponent).is_pos_integer() ||
+                            !is_ex_exactly_of_type(ex_to_power(b).basis,add) ||
+                            !is_ex_exactly_of_type(ex_to_power(b).basis,mul) ||
+                            !is_ex_exactly_of_type(ex_to_power(b).basis,power));
+               if (is_ex_exactly_of_type(b,mul))
+                       term.push_back(expand_mul(ex_to_mul(b),numeric(n-k_cum[m-2])));
+               else
+                       term.push_back(power(b,n-k_cum[m-2]));
+               
+               numeric f = binomial(numeric(n),numeric(k[0]));
+               for (l=1; l<m-1; l++)
+                       f *= binomial(numeric(n-k_cum[l-1]),numeric(k[l]));
+               
+               term.push_back(f);
+               
+               /*
+               cout << "begin term" << endl;
+               for (int i=0; i<m-1; i++) {
+                       cout << "k[" << i << "]=" << k[i] << endl;
+                       cout << "k_cum[" << i << "]=" << k_cum[i] << endl;
+                       cout << "upper_limit[" << i << "]=" << upper_limit[i] << endl;
+               }
+               for (exvector::const_iterator cit=term.begin(); cit!=term.end(); ++cit) {
+                       cout << *cit << endl;
+               }
+               cout << "end term" << endl;
+               */
+               
+               // TODO: optimize this
+               sum.push_back((new mul(term))->setflag(status_flags::dynallocated));
+               
+               // increment k[]
+               l = m-2;
+               while ((l>=0)&&((++k[l])>upper_limit[l])) {
+                       k[l] = 0;    
+                       l--;
+               }
+               if (l<0) break;
+               
+               // recalc k_cum[] and upper_limit[]
+               if (l==0)
+                       k_cum[0] = k[0];
+               else
+                       k_cum[l] = k_cum[l-1]+k[l];
+               
+               for (int i=l+1; i<m-1; i++)
+                       k_cum[i] = k_cum[i-1]+k[i];
+               
+               for (int i=l+1; i<m-1; i++)
+                       upper_limit[i] = n-k_cum[i-1];
+       }
+       return (new add(sum))->setflag(status_flags::dynallocated |
+                                                                  status_flags::expanded );
 }
 
 
@@ -719,128 +723,124 @@ ex power::expand_add(const add & a, int n) const
  *  @see power::expand_add */
 ex power::expand_add_2(const add & a) const
 {
-    epvector sum;
-    unsigned a_nops=a.nops();
-    sum.reserve((a_nops*(a_nops+1))/2);
-    epvector::const_iterator last=a.seq.end();
-
-    // power(+(x,...,z;c),2)=power(+(x,...,z;0),2)+2*c*+(x,...,z;0)+c*c
-    // first part: ignore overall_coeff and expand other terms
-    for (epvector::const_iterator cit0=a.seq.begin(); cit0!=last; ++cit0) {
-        const ex & r=(*cit0).rest;
-        const ex & c=(*cit0).coeff;
-        
-        GINAC_ASSERT(!is_ex_exactly_of_type(r,add));
-        GINAC_ASSERT(!is_ex_exactly_of_type(r,power)||
-               !is_ex_exactly_of_type(ex_to_power(r).exponent,numeric)||
-               !ex_to_numeric(ex_to_power(r).exponent).is_pos_integer()||
-               !is_ex_exactly_of_type(ex_to_power(r).basis,add)||
-               !is_ex_exactly_of_type(ex_to_power(r).basis,mul)||
-               !is_ex_exactly_of_type(ex_to_power(r).basis,power));
-
-        if (are_ex_trivially_equal(c,_ex1())) {
-            if (is_ex_exactly_of_type(r,mul)) {
-                sum.push_back(expair(expand_mul(ex_to_mul(r),_num2()),_ex1()));
-            } else {
-                sum.push_back(expair((new power(r,_ex2()))->setflag(status_flags::dynallocated),
-                                     _ex1()));
-            }
-        } else {
-            if (is_ex_exactly_of_type(r,mul)) {
-                sum.push_back(expair(expand_mul(ex_to_mul(r),_num2()),
-                                     ex_to_numeric(c).power_dyn(_num2())));
-            } else {
-                sum.push_back(expair((new power(r,_ex2()))->setflag(status_flags::dynallocated),
-                                     ex_to_numeric(c).power_dyn(_num2())));
-            }
-        }
-            
-        for (epvector::const_iterator cit1=cit0+1; cit1!=last; ++cit1) {
-            const ex & r1=(*cit1).rest;
-            const ex & c1=(*cit1).coeff;
-            sum.push_back(a.combine_ex_with_coeff_to_pair((new mul(r,r1))->setflag(status_flags::dynallocated),
-                                                          _num2().mul(ex_to_numeric(c)).mul_dyn(ex_to_numeric(c1))));
-        }
-    }
-
-    GINAC_ASSERT(sum.size()==(a.seq.size()*(a.seq.size()+1))/2);
-
-    // second part: add terms coming from overall_factor (if != 0)
-    if (!a.overall_coeff.is_equal(_ex0())) {
-        for (epvector::const_iterator cit=a.seq.begin(); cit!=a.seq.end(); ++cit) {
-            sum.push_back(a.combine_pair_with_coeff_to_pair(*cit,ex_to_numeric(a.overall_coeff).mul_dyn(_num2())));
-        }
-        sum.push_back(expair(ex_to_numeric(a.overall_coeff).power_dyn(_num2()),_ex1()));
-    }
-        
-    GINAC_ASSERT(sum.size()==(a_nops*(a_nops+1))/2);
-    
-    return (new add(sum))->setflag(status_flags::dynallocated |
-                                   status_flags::expanded );
+       epvector sum;
+       unsigned a_nops = a.nops();
+       sum.reserve((a_nops*(a_nops+1))/2);
+       epvector::const_iterator last = a.seq.end();
+       
+       // power(+(x,...,z;c),2)=power(+(x,...,z;0),2)+2*c*+(x,...,z;0)+c*c
+       // first part: ignore overall_coeff and expand other terms
+       for (epvector::const_iterator cit0=a.seq.begin(); cit0!=last; ++cit0) {
+               const ex & r = (*cit0).rest;
+               const ex & c = (*cit0).coeff;
+               
+               GINAC_ASSERT(!is_ex_exactly_of_type(r,add));
+               GINAC_ASSERT(!is_ex_exactly_of_type(r,power) ||
+                            !is_ex_exactly_of_type(ex_to_power(r).exponent,numeric) ||
+                            !ex_to_numeric(ex_to_power(r).exponent).is_pos_integer() ||
+                            !is_ex_exactly_of_type(ex_to_power(r).basis,add) ||
+                            !is_ex_exactly_of_type(ex_to_power(r).basis,mul) ||
+                            !is_ex_exactly_of_type(ex_to_power(r).basis,power));
+               
+               if (are_ex_trivially_equal(c,_ex1())) {
+                       if (is_ex_exactly_of_type(r,mul)) {
+                               sum.push_back(expair(expand_mul(ex_to_mul(r),_num2()),
+                                                    _ex1()));
+                       } else {
+                               sum.push_back(expair((new power(r,_ex2()))->setflag(status_flags::dynallocated),
+                                                    _ex1()));
+                       }
+               } else {
+                       if (is_ex_exactly_of_type(r,mul)) {
+                               sum.push_back(expair(expand_mul(ex_to_mul(r),_num2()),
+                                                    ex_to_numeric(c).power_dyn(_num2())));
+                       } else {
+                               sum.push_back(expair((new power(r,_ex2()))->setflag(status_flags::dynallocated),
+                                                    ex_to_numeric(c).power_dyn(_num2())));
+                       }
+               }
+                       
+               for (epvector::const_iterator cit1=cit0+1; cit1!=last; ++cit1) {
+                       const ex & r1 = (*cit1).rest;
+                       const ex & c1 = (*cit1).coeff;
+                       sum.push_back(a.combine_ex_with_coeff_to_pair((new mul(r,r1))->setflag(status_flags::dynallocated),
+                                                                     _num2().mul(ex_to_numeric(c)).mul_dyn(ex_to_numeric(c1))));
+               }
+       }
+       
+       GINAC_ASSERT(sum.size()==(a.seq.size()*(a.seq.size()+1))/2);
+       
+       // second part: add terms coming from overall_factor (if != 0)
+       if (!a.overall_coeff.is_zero()) {
+               for (epvector::const_iterator cit=a.seq.begin(); cit!=a.seq.end(); ++cit) {
+                       sum.push_back(a.combine_pair_with_coeff_to_pair(*cit,ex_to_numeric(a.overall_coeff).mul_dyn(_num2())));
+               }
+               sum.push_back(expair(ex_to_numeric(a.overall_coeff).power_dyn(_num2()),_ex1()));
+       }
+       
+       GINAC_ASSERT(sum.size()==(a_nops*(a_nops+1))/2);
+       
+       return (new add(sum))->setflag(status_flags::dynallocated | status_flags::expanded);
 }
 
 /** Expand factors of m in m^n where m is a mul and n is and integer
  *  @see power::expand */
 ex power::expand_mul(const mul & m, const numeric & n) const
 {
-    if (n.is_equal(_num0()))
-        return _ex1();
-    
-    epvector distrseq;
-    distrseq.reserve(m.seq.size());
-    epvector::const_iterator last = m.seq.end();
-    epvector::const_iterator cit = m.seq.begin();
-    while (cit!=last) {
-        if (is_ex_exactly_of_type((*cit).rest,numeric)) {
-            distrseq.push_back(m.combine_pair_with_coeff_to_pair(*cit,n));
-        } else {
-            // it is safe not to call mul::combine_pair_with_coeff_to_pair()
-            // since n is an integer
-            distrseq.push_back(expair((*cit).rest,
-                                      ex_to_numeric((*cit).coeff).mul(n)));
-        }
-        ++cit;
-    }
-    return (new mul(distrseq,ex_to_numeric(m.overall_coeff).power_dyn(n)))
-        ->setflag(status_flags::dynallocated);
+       if (n.is_zero())
+               return _ex1();
+       
+       epvector distrseq;
+       distrseq.reserve(m.seq.size());
+       epvector::const_iterator last = m.seq.end();
+       epvector::const_iterator cit = m.seq.begin();
+       while (cit!=last) {
+               if (is_ex_exactly_of_type((*cit).rest,numeric)) {
+                       distrseq.push_back(m.combine_pair_with_coeff_to_pair(*cit,n));
+               } else {
+                       // it is safe not to call mul::combine_pair_with_coeff_to_pair()
+                       // since n is an integer
+                       distrseq.push_back(expair((*cit).rest, ex_to_numeric((*cit).coeff).mul(n)));
+               }
+               ++cit;
+       }
+       return (new mul(distrseq,ex_to_numeric(m.overall_coeff).power_dyn(n)))->setflag(status_flags::dynallocated);
 }
 
 /*
 ex power::expand_commutative_3(const ex & basis, const numeric & exponent,
-                             unsigned options) const
+                               unsigned options) const
 {
-    // obsolete
+       // obsolete
 
-    exvector distrseq;
-    epvector splitseq;
+       exvector distrseq;
+       epvector splitseq;
 
-    const add & addref=static_cast<const add &>(*basis.bp);
+       const add & addref=static_cast<const add &>(*basis.bp);
 
-    splitseq=addref.seq;
-    splitseq.pop_back();
-    ex first_operands=add(splitseq);
-    ex last_operand=addref.recombine_pair_to_ex(*(addref.seq.end()-1));
-    
-    int n=exponent.to_int();
-    for (int k=0; k<=n; k++) {
-        distrseq.push_back(binomial(n,k)*power(first_operands,numeric(k))*
-                           power(last_operand,numeric(n-k)));
-    }
-    return ex((new add(distrseq))->setflag(status_flags::expanded |
-                                           status_flags::dynallocated )).
-           expand(options);
+       splitseq=addref.seq;
+       splitseq.pop_back();
+       ex first_operands=add(splitseq);
+       ex last_operand=addref.recombine_pair_to_ex(*(addref.seq.end()-1));
+       
+       int n=exponent.to_int();
+       for (int k=0; k<=n; k++) {
+               distrseq.push_back(binomial(n,k) * power(first_operands,numeric(k))
+                                                * power(last_operand,numeric(n-k)));
+       }
+       return ex((new add(distrseq))->setflag(status_flags::expanded | status_flags::dynallocated)).expand(options);
 }
 */
 
 /*
 ex power::expand_noncommutative(const ex & basis, const numeric & exponent,
-                                unsigned options) const
+                                                               unsigned options) const
 {
-    ex rest_power=ex(power(basis,exponent.add(_num_1()))).
-                  expand(options | expand_options::internal_do_not_expand_power_operands);
+       ex rest_power = ex(power(basis,exponent.add(_num_1()))).
+                       expand(options | expand_options::internal_do_not_expand_power_operands);
 
-    return ex(mul(rest_power,basis),0).
-           expand(options | expand_options::internal_do_not_expand_mul_operands);
+       return ex(mul(rest_power,basis),0).
+              expand(options | expand_options::internal_do_not_expand_mul_operands);
 }
 */
 
@@ -852,20 +852,11 @@ ex power::expand_noncommutative(const ex & basis, const numeric & exponent,
 
 unsigned power::precedence = 60;
 
-//////////
-// global constants
-//////////
-
-const power some_power;
-const type_info & typeid_power=typeid(some_power);
-
 // helper function
 
 ex sqrt(const ex & a)
 {
-    return power(a,_ex1_2());
+       return power(a,_ex1_2());
 }
 
-#ifndef NO_NAMESPACE_GINAC
 } // namespace GiNaC
-#endif // ndef NO_NAMESPACE_GINAC